The present invention relates to nail structures, and particularly to a nail structure having a wall nail casing and a hammer nail, wherein when the hammer nail is beaten into a central axial hole of the wall nail casing, the hammer nail expands the central axial hole outwards to prevent the hammer nail from colliding the distal end of the wall nail casing.
Referring to FIGS. 1 and 2, a prior art nail structure is illustrated. In using, a wall nail casing 3 is fixed to a wall and a hammer nail 4 is beaten into the wall nail casing 3. A center of the wall nail casing 3 is formed with a tapered central axial hole 31 which is reduced to one distal end thereof far way from an inlet of the hammer nail 4. When the hammer nail 4 is beaten into the central axial hole 31, the hammer nail 4 will expand the central axial hole 31 of the wall nail casing 3 so as to be embedded into the central axial hole 31. However, this prior art wall nail casing has the following disadvantages:
The central point can not be corrected: In manufacturing the wall nail casing 3, in the mold of the manufacturing the wall nail casing, a coaxial pin shorter than the length of the wall nail casing is inserted into the mold. When forming the wall nail casing, since the wall nail casing is a long tube, as pressing the wall nail casing, an overlarge pressure on the central axial hole 31 will shift the coaxial pin when the coaxial pin is tilt so that the central axial hole of the wall nail casing can not be aligned to the central axis itself. Thereby, the hammer nail is buckled in the inner side of the wall nail casing, and thus it is unsuccessful to beat the hammer nail into the wall nail casing, as illustrated in FIG. 2.
The hammer nail easily deforms. This is because in the prior art, only one coaxial pin is inserted into the wall nail casing 3, and the pin is shorted than the wall nail casing. Thus the distal end 32 of the wall nail casing is closed. When the hammer nail 4 applies a force to the wall nail casing 3 so that the outer side of the hammer nail 4 is extruded into the central axial hole 31. Since the distal end 32 is closed, the expanding force is non-uniform and therefore, and the push force is insufficient. It becomes difficult to expand the central axial hole 31 of the wall nail casing. Thereby, it is easy that the tip of the hammer nail 4 will deform as it is beaten into the wall nail casing. Thus the hammer nail 4 provides an insufficient push force and thus the function thereof is reduced.
The edge of the hammer nail 4 is not smooth, and the tip 41 of the prior art hammer nail 4 is not smooth and thus is formed because an uneven edge 411 will rub the inner edge of the wall nail casing. Thereby, the outer diameter of the wall nail casing becomes coarse and cannot be inserted into the wall.
Accordingly the primary object of the present invention is to provide nail structure which comprises a wall nail casing a center of the wall nail casing being formed with a tapered central axial hole which is reduced toward a distal end thereof; two sides of the distal end of the wall nail casing being formed with respective slots; and one end of the central axial hole being an through opening and another end thereof being an inlet; a hammer nail capable of inserting into the central axial hole; and a plurality of semi-round enhancing ribs are on an inner surface of the central axial hole of the wall nail casing; a front end of each enhancing rib being reduced toward one inlet of the central axial hole for receiving the hammer nail easily.